On 19.07.2023 01:08, Rob Herring wrote:
On Sat, Jul 15, 2023 at 11:30:43AM +0300, Maxim Kochetkov wrote:
The trigger-start/stop properties allows to specify DAI link
trigger ordering method.
Obviously. Why do you need these? What problem does it solve?
It allows using simple card for some DMA-based CPU component which
requires different start/stop sequence (stop DMA before CPU component,
start DMA after CPU component).
There are a lot of boards which have no audio codec on board. It has
only I2S/TDM/etc... and you can attach any external codec on its pins.
It looks like simple audio card is enough for this cases. It is much
better than to copy-paste simple audio card code to the new custom
driver with new combination of CPU/codec.
I don't think these belong in simple-card. What's next? What if you need
delays between each step? This is the problem with 'simple' or 'generic'
bindings. It's a never ending addition of properties which are not well
thought out.
Can you please suggest the better way to specify start/stop trigger
order via DT?
+ trigger-start:
+ description: |-
+ Start trigger ordering method:
+ default: Link->Component->DAI
+ ldc: Link->DAI->Component
+ $ref: /schemas/types.yaml#/definitions/string
+ items:
+ enum:
+ - default
Why do you need a value of 'default'? What's the default when the
property is not present?
It comes from
enum snd_soc_trigger_order {
SND_SOC_TRIGGER_ORDER_DEFAULT = 0,
SND_SOC_TRIGGER_ORDER_LDC,
SND_SOC_TRIGGER_ORDER_MAX,
};
default value is 0 (SND_SOC_TRIGGER_ORDER_DEFAULT)
format:
description: audio format.
items:
@@ -210,6 +232,10 @@ properties:
maxItems: 1
simple-audio-card,mic-det-gpio:
maxItems: 1
+ simple-audio-card,trigger-start:
+ $ref: "#/definitions/trigger-start"
+ simple-audio-card,trigger-stop:
+ $ref: "#/definitions/trigger-stop"
Don't continue this 'simple-audio-card,' prefix pattern. With it, no
other binding can use these properties.
Ok.
patternProperties:
"^simple-audio-card,cpu(@[0-9a-f]+)?$":
@@ -259,6 +285,11 @@ patternProperties:
maxItems: 1
mic-det-gpio:
maxItems: 1
+ trigger-start:
+ $ref: "#/definitions/trigger-start"
+ trigger-stop:
+ $ref: "#/definitions/trigger-stop"
+
Should I keep only this section?